Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 17 1 2025 03 03 8 18 Mohammad Javad SheikhMozafari Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran | Students’ Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran Fatemeh MirnajafiZadeh Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Ali Mohsenian Department of Occupational Health and Safety Engineering, School of health, Shiraz university of medical sciences, Shiraz, Iran 2024 09 23 2024 11 11 Background: Non-standard work shifts are one of the main risk factors for physical and mental disorders. This study aimed to evaluate the reliability of the Shift Work Disorder Screening (SWDS) questionnaire and examine the effect of shift work on the quality of life and well-being of nurses in a hospital in Iran. Methods: This study was conducted on 85 nurses, of which 41 and 44 had shift and non-shift work, respectively. The SWDS was used to evaluate shift disorders, and the WHO-5 questionnaire was used to assess the well-being of nurses. ICC and alpha coefficients were used to evaluate the reliability. T-test and chi-square tests were used to evaluate the differences between demographic characteristics and questionnaire responses between the two groups of nurses. Results: The SWDS reliability using Cronbach’s alpha and ICC were 0.913 and 0.845, respectively. Fifty-four percent of nurses were high risk, and 46% were low risk, regarding the SWD score. About 59% of shift workers were dissatisfied with their sleep. Nurses who had done shift work for less than a year and fewer than three days per week were less likely to experience disorders. There was a significant relationship between WHO score and SWD risk. Conclusion: The SWD risk affects the well-being of individuals. The SWDS is a proper tool for shift work disorder risk assessment, and it can be used to assess the risk of adverse safety, health, and performance effects of SWD. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/642 https://ijoh.tums.ac.ir/index.php/ijoh/article/download/642/822